Hale 4DK Series User Manual
Page 18
18
Manual p/n: 029-0020-79-0
4DK Series Pumps
SUGGESTED CORRECTIVE ACTION
CONDITION
POSSIBLE
CAUSE
PUMP LOSES
PRIME OR WILL
NOT PRIME -
continued
Air trapped in
suction line -
continued
Pump pressure too
low when nozzle is
opened
Air leaks
●
If trap in hose is unavoidable, repeated priming may be
necessary to eliminate air pocket in suction hose.
●
Prime the pump again and maintain higher pump pressure
while opening the discharge valve slowly.
●
Attempt to locate and correct air leaks.
●
The suction side relief valve can leak. Plug the valve outlet
connection and retest.
INSUFFICIENT
PUMP
CAPACITY
Insufficient engine
power
Relief valve improp-
erly set - if so
equipped
Engine governor set
incorrectly - if so
equipped
Truck transmission
is in wrong gear, or
clutch is slipping
Air leaks
●
Engine power check or tune up may be required for peak
engine and pump performance.
●
If the relief valve pressure is set too low it allows the valve to
open and bypass fluid.
●
Reset the relief valve pressure accordingly.
●
If the engine governor is set too low when on automatic, the
engine speed decelerates before the desired pressure is
reached.
●
Reset the governor per manufacturer's procedures.
●
Recheck the pumping procedures for the recommended
transmission or gear range. See truck manual for assistance.
●
Use mechanical speed counter on the pump panel to check
speed against possible clutch or transmission slipping or
inaccurate tachometer. (Check the truck manual for possible
speed counter ratio.)
●
See Possible Causes "Air leaks" under PUMP LOSES PRIME
OR WILL NOT PRIME, beginning on page 17.
INSUFFICIENT
PRESSURE
●
See previous section: Insufficient Pump Capacity.
ENGINE SPEEDS
TOO HIGH FOR
REQUIRED
CAPACITY OR
PRESSURE
Chart continued on
next page
Truck transmission
in wrong range or
gear
●
Check recommended procedures for correct transmission
selection. (See truck manual for assistance.)